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Présentation de la transition vitreuse de l'eau et comparaison avec des verres hypertrempés non organiques.

Clarifying the glass-transition behaviour of water by comparison with hyperquenched inorganic glasses.

Auteurs : YUE Y., ANGELL C. A.

Type d'article : Article

Résumé

The formation of glasses is normal for substances that remain liquid over a wide temperature range ('good glassformers') and can be induced for most liquids if cooling is fast enough to bypass crystallization. During reheating but still below the melting point, good glassformers exhibit glass transitions as they abruptly transform into supercooled liquids, whereas other substances transform directly from the glassy to the crystalline state. Whether water exhibits a glass transition before crystallization has been much debated over five decades. For the last 20 years, the existence of a glass transition at 136 K has been widely accepted, but the transition exhibits qualities difficult to reconcile with our current knowledge of glass transitions. The authors report detailed calorimetric characterizations of hyperquenched inorganic glasses that, when heated, do not crystallize before reaching their glass transition temperatures. The authors compare our results to the behaviour of glassy water and find that small endothermic effects, such as that attributed to the glass transition of water, are only a 'shadow' of the real glass transition occurring at higher temperatures, thus substantiating the conclusion that the glass transition of water cannot be probed directly.

Détails

  • Titre original : Clarifying the glass-transition behaviour of water by comparison with hyperquenched inorganic glasses.
  • Identifiant de la fiche : 2004-1558
  • Langues : Anglais
  • Source : Nature - vol. 427 - n. 6976
  • Date d'édition : 19/02/2004
  • Document disponible en consultation à la bibliothèque du siège de l'IIF uniquement.

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